Code ran out of execution time

Why does the creation of this list in the coding environment cause a "Code ran out of execution time" error?
the same list is created in two different ways, but one creation leads to that error.
method one (leads to an error):

from itertools import permutations
nums = [2, 1, 0, 0, -1, -1, -2, -2, -3, 7]
perms = list(permutations(nums))

method two (no error):

from itertools import permutations
nums = [2, 1, 0, 0, -1, -1, -2, -2, -3, 7]
perms = permutations(nums)

the first method seems to create a list from a list, but the result seems to be the same.
So where does the error happens?

(to check if the output is the same, a permutation of up to 9 values can be used.
the runtime error happens when at least 10 values are permutated.)

Easy Math Editor

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`2 \times 3`	$2 \times 3$
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`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$

Comments

@Carsten Kaminski have u seen this in the daily challenge of Nov 3rd? if you can spare some time: can you help me to understand why "perms = list(permutations(nums))" cause a runtime error?

num IC - 7 months, 1 week ago

the code is correct in both ways. The first snippet creates a very huge list with 10! elements; lists handling is very slow in Python (lists in Python are more dynamic arrays or linked lists). The second one is an itertools object with generates output by demand; type(perms): <class 'itertools.permutations'>

A Former Brilliant Member - 7 months, 1 week ago

ok. i thought both create lists. i will check the docu of the datatypes to understand the difference.
when i print them (based on 4 elements), both show 4! elements. is this wrong?

num IC - 7 months, 1 week ago

@Num Ic – do you mean printing in a loop: for p in perms...?

A Former Brilliant Member - 7 months, 1 week ago

@A Former Brilliant Member – i did this:

a = [1,2,3,6]
c = permutations(a)
b = list(permutations(a))
print(a)
print("b:", *b)
print("c:", *c)

num IC - 7 months, 1 week ago

@Num Ic – you used the unpacking operator to unpack all values from an iterator (e. g. list oder itertools object)

A Former Brilliant Member - 7 months, 1 week ago

and by the way: don't use Brilliant's Coding Environment; the interpreter is very slooooooooooooow. Try repl.it

A Former Brilliant Member - 7 months, 1 week ago

good hint ty.

num IC - 7 months, 1 week ago

there is another Carsten Kaminski here, same name, but not your picture.
you always create very impressive code. today i thought there is no way to solve the triangle problem with good looking code. but u proved me wrong: even for this problem u created very cool code. ty for presenting your creative way of coding. to read your codes is a great enrichment.

num IC - 7 months, 1 week ago

Thank you for the hint. I deleted the second account made by mistake....

A Former Brilliant Member - 7 months ago

@A Former Brilliant Member – and by the way: thanks for the compliment! But I am only an experienced beginner...

A Former Brilliant Member - 7 months ago

hello Carsten, i tried to re-read your solution for "How Many Ones", but it is vanished.
did u delete it? or is there a bug?

num IC - 7 months ago

Hi, I was not really satisfied with the code... print(f"{str(bin(p:=int('1'*9,2) * int('11', 2)).count('1'))} ones in {p:b}")

A Former Brilliant Member - 7 months ago

@A Former Brilliant Member – ty. i m glad to hear that you are ok.

num IC - 7 months ago

Umm... You can use PythonTutor's Visualiser as well

Atin Gupta - 3 months, 2 weeks ago

good hint. thank you.
i tried the code for todays solution that just executes all 10000 cases and got this:

Stopped after running 1000 steps. Please shorten your code, since Python Tutor is not designed to handle long-running code.

i reduced the code and saw that it can be run step by step.
this is very helpful. thank you

num IC - 3 months, 2 weeks ago

@Num Ic – Welcome. I use the visualiser to see where I made a mistake in the code by (kind of) zooming it into the part which isn't functioning correctly

Atin Gupta - 3 months, 2 weeks ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$